Higher levels of Vitamin D may lower your chances of Breast Cancer

But JoAnn Manson, chief of the division of preventive medicine at Brigham and Women's Hospital in Boston, urged caution about the results, saying the "jury is still out" on whether high vitamin D levels can decrease the risk of colorectal cancer.

The American Cancer Society predicts more than 140-thousand new cases of Colorectal Cancer will be diagnosed this year. Manson, who is leading such a trial, also said blood levels of vitamin D can be affected by outdoor physical activity, obesity, overall nutritional intake and other factors. The combined data included more than 5000 women, aged 55 and older, who had a broad range of vitamin D blood levels. According to a new study, great amounts of vitamin D may reduce the risks of developing breast cancer in women.

This study covered 12,813 adult people in Europe, Asia and the U.S. and it analyzed people with colorectal cancer and people of a similar age and race who did not have cancer.

Higher blood concentrations of vitamin D are linked to a lower risk of colorectal cancer, especially in women, according to a large new study from researchers at Harvard T.H. Chan School of Public Health, the National Cancer Institute, the American Cancer Society, and 20 other medical centers and organizations around the world.

Participants were free of cancer at enrollment and were followed for a mean period of four years.

The authors of the new study say that may be because the studies were too small, the supplements weren't taken for long enough, or the subjects didn't fully comply - because now, they claim, they have the clearest evidence yet that there is a concrete link. "Further research is needed on whether high 25 (OH) D levels might prevent premenopausal breast cancer", said Cedric F. Garland from UC-San Diego.

This study is yet another reminder to prioritize loading up on vitamin D, since around three quarters of Americans and a fifth of Brits are deficient - but while the vitamin is hard to find in natural foods, experts warn to scrutinize supplements that may not have been tested rigorously.

They concluded that vitamin D does indeed appear to provide protection against colon cancer, particularly for women. Heavy doses of vitamin D can be toxic.

People also get vitamin D from fortified foods like milk, cereal and orange juice, and from fatty fish like salmon, tuna, trout and swordfish, McCullough said. Vitamin D is often called the "sunshine" vitamin, because exposure to sunlight can stimulate production of the vitamin.